Preparation and Crystal Structures of Th5Fe19P12 and ThFe4P2

1992 ◽  
Vol 47 (11) ◽  
pp. 1521-1528 ◽  
Author(s):  
Jörg H. Albering ◽  
Wolfgang Jeitschko

The new compounds Th5Fe19P12 and ThFe4P2 were prepared by reaction of the elemental components in a tin flux and their crystal structures were determined from single-crystal X-ray data. Th5Fe19P12 crystallizes with a new monoclinic structure type: C2/m, a = 2920.3(3), b = 379.18(3), c = 931.48(8) pm, β = 103.36(1)°, Z = 2, R = 0.031. ThFe4P2 is isotypic with SmNi4P2: P nnm, a = 1448.9(2), b = 1074.7(2), c = 376.98(4) pm, Z = 6, R = 0.030. Both compounds belong to the large family of structures with a metal : nonmetal ratio of exactly or nearly 2:1. In these phosphides all phosphorus atoms have nine metal neighbors: six are forming a trigonal prism with three additional neighbors capping the rectangular faces of the prism. In both structures the thorium atoms have trigonal prismatic or octahedral phosphorus coordination. Most iron atoms have the usual tetrahedral phosphorus environment. In addition, the structure of Th5Fe19P12 has iron atoms in rectangular and distorted square pyramidal phosphorus coordination, while the structure of ThFe4P2 contains iron atoms with only two or three phosphorus neighbors.

2015 ◽  
Vol 70 (7) ◽  
pp. 497-503 ◽  
Author(s):  
Nataliya Dominyuk ◽  
Vasyl’ I. Zaremba ◽  
Ute Ch. Rodewald ◽  
Rainer Pöttgen

AbstractThe ternary indide Nd39Ir10.98In36.02 was synthesized by arc-melting and characterized by single crystal X-ray diffraction. Nd39Ir10.98In36.02 crystallizes with a new structure type: Pearson code oP172, Pbam, a = 3175.4(6), b = 3762.5(8), c = 378.02(8) pm, wR2 = 0.0828, 5544 F2 values, and 262 variables. Although the structure contains 44 crystallographically independent sites, it can easily be explained as an intergrowth structure of CsCl and AlB2 related slabs. The larger indium atoms fill all distorted CsCl slabs. The trigonal prismatic (AlB2) slabs have no uniform size. The larger ones are filled by indium and the smaller ones by the iridium atoms. Additionally, one trigonal prism shows a mixed occupancy by indium and iridium. The crystal chemistry of Nd39Ir10.98In36.02 is discussed in the context of other intergrowth structures with the same simple slabs.


2018 ◽  
Vol 74 (6) ◽  
pp. 721-727 ◽  
Author(s):  
Karolina Schwendtner ◽  
Uwe Kolitsch

The crystal structures of hydrothermally synthesized (T= 493 K, 7–9 d) rubidium aluminium bis[hydrogen arsenate(V)], RbAl(HAsO4)2, caesium iron bis[hydrogen arsenate(V)], CsFe(HAsO4)2, rubidium dialuminium arsenic(V) hexakis[hydrogen arsenate(V)], RbAl2As(HAsO4)6, and caesium diiron arsenic(V) hexakis[hydrogen arsenate(V)], CsFe2As(HAsO4)6, were solved by single-crystal X-ray diffraction. The four compounds with the general formulaM+M3+(HAsO4)2adopt the RbFe(HPO4)2structure type (R\overline{3}c) and a closely related new structure type, which is characterized by a different stacking order of the building units, leading to noncentrosymmetric space-group symmetryR32. The second new structure type, with the general formulaM+M3+2As(HAsO4)6(R\overline{3}c), is also a modification of the RbFe(HPO4)2structure type, in which one third of theM3+O6octahedra are replaced by AsO6octahedra, and two thirds of the voids in the structure, which are usually filled byM+cations, remain empty to achieve charge balance.


2018 ◽  
Vol 74 (8) ◽  
pp. 1163-1167 ◽  
Author(s):  
Karolina Schwendtner ◽  
Uwe Kolitsch

The crystal structures of hydrothermally synthesized (T = 493 K, 7 d) thallium(I) digallium arsenic(V) hexakis[hydrogenarsenate(V)], TlGa2As(HAsO4)6, caesium digallium arsenic(V) hexakis[hydrogenarsenate(V)], CsGa2As(HAsO4)6, and caesium dialuminium arsenic(V) hexakis[hydrogenarsenate(V)], CsAl2As(HAsO4)6, were solved by single-crystal X-ray diffraction. The three compounds are isotypic and adopt the structure type of RbAl2As(HAsO4)6 (R\overline{3}c), which itself represents a modification of the RbFe(HPO4)2 structure type and consists of a tetrahedral–octahedral framework in which the slightly disordered M + cations are located in channels. The three new compounds contain AsO6 octahedra assuming the topological role of M 3+O6 octahedra. The As—O bond lengths are among the shortest As—O bond lengths known so far in AsO6 octahedra.


1991 ◽  
Vol 46 (5) ◽  
pp. 566-572 ◽  
Author(s):  
Axel Gudat ◽  
Peter Höhn ◽  
Rüdiger Kniep ◽  
Albrecht Rabenau

The isotypic ternary compounds Ba3[MoN4] and Ba3[WN4] were prepared by reaction of the transition metals with barium (Ba3N2, resp.) under nitrogen. The crystal structures were determined by single crystal X-ray diffraction: Ba3[MoN4] (Ba3[WN4]): Pbca; Z = 8; a = 1083.9(3) pm (1091.8(3) pm), b = 1030.3(3) pm (1037.5(3) pm), c = 1202.9(3) pm (1209.2(4) pm). The structures contain isolated tetrahedral anions [MN4]6- (M = Mo, W) which are arranged in form of slightly distorted hexagonal layers and which are stacked along [010] with the sequence (···AB···). Two of the three Ba atoms are situated between, the third one is placed within the layers of [MN4]-groups. In this way the structures can be derived from the Na3As structure type.


2006 ◽  
Vol 61 (7) ◽  
pp. 779-784 ◽  
Author(s):  
Ol’ga Stel’makhovych ◽  
Yurij Kuz’ma

The crystal structures of several new compounds have been determined using X-ray analysis. The intermetallic compound HoZn5Al3 (a = 8.586(3), c = 16.538(5) Å , RF = 0.0413, RW = 0.0521) has its own structure type (space group I4/mmm), which has been found for the first time. The following compounds are isostructural with the previous one: YZn5.52Al2.48 (a = 8.6183(1), c = 16.5048(3) Å , RI = 0.078, RP = 0.116), DyZn4.96Al3.04 (a = 8.5887(1), c = 16.5002(3) Å , RI = 0.077, RP = 0.114), ErZn5.37Al2.63 (a = 8.5525(2), c =16.3997(5) Å , RI = 0.081, RP = 0.111), TmZn5.64Al2.36 (a = 8.70429(8), c = 16.3943(4) Å , RI = 0.088, RP = 0.095), LuZn5.58Al2.42 (a = 8.5616(1), c= 16.3052(3) Å , RI =0.081, RP =0.101). The intermetallic compound Yb4Zn20.3Al12.7 (a = 8.6183(1), c = 16.5048(3) Å , RI = 0.085, RP = 0.112) adopts the Yb8Cu17Al49 - type structure (space group I4/mmm). The relationship between the HoZn5Al3-type and the Yb8Cu17Al49-type structures is discussed.


1992 ◽  
Vol 47 (9) ◽  
pp. 1203-1212 ◽  
Author(s):  
Jörg Neuhausen ◽  
Karl-Ludwig Stork ◽  
Elisabeth Potthoff ◽  
Wolfgang Tremel

Nb0.89Fe0.93Te2 and Ta0.77Fe0.90Te2 were prepared by chemical transport reactions. The crystal structures of both compounds were determined using X-ray single crystal methods. The structures of the layer compounds Nb0.89Fe0.93Te2 (Pmna, Z = 2, a = 7.951(1) Å, b = 7.241(1) A, c = 6.233(1) Å) and Ta0.77Fe0.90Te2 (Pmna, Z = 2, a = 7.890(2) Å, b = 7.252(2) Å, c = 6.192(1) Å) are based on a hexagonal close packing of Te atoms. Approximately one-half of the octahedral holes in this packing are occupied by Nb (Ta) atoms, about one-quarter of the tetrahedral holes are occupied by Fe atoms. The relationship to the NiAs structure type is discussed.


2009 ◽  
Vol 65 (5) ◽  
pp. 551-557 ◽  
Author(s):  
Kenny Ståhl ◽  
Rolf W. Berg ◽  
K. Michael Eriksen ◽  
Rasmus Fehrmann

The crystal structures of Cs2S2O7 at 120 and 273 K have been determined from X-ray single-crystal data. Caesium disulfate represents a new structure type with a uniquely high number of independent formula units at 120 K: In one part caesium ions form a tube surrounding the disulfate ions, [Cs8(S2O7)6+] n ; in the other part a disulfate double-sheet sandwiches a zigzagging caesium ion chain, [Cs2(S2O7)6−] n . Caesium disulfate shows an isostructural order–disorder transition between 230 and 250 K, where two disulfate groups become partially disordered above 250 K. The Cs+-ion arrangement shows a remarkable similarity to the high-pressure RbIV metal structure.


2011 ◽  
Vol 66 (1) ◽  
pp. 21-26
Author(s):  
Olaf Reckeweg ◽  
Francis J. DiSalvo

Single crystals of Sr2H3I andBa5H2I3.9(2)O2 were obtained by reacting Sr or Ba, respectively, with dried and sublimed NH4I in a 4 : 1 molar ratio in silica-jacketed Nb ampoules for 13 h at 1200 K. The crystal structures of the new compounds have been determined by means of single-crystal X-ray diffraction. Sr2H3I crystallizes in a stuffed anti-CdI2 structure isotypic to Ba2H3Cl in the space group P3m1 (no. 164) with the lattice parameters a = 426.0(1) and c = 774.9(2) pm, while Ba5H2I3.9(2)O2 crystallizes in a new structure type in the space group Cmcm (no. 63) with the lattice parameters a = 1721.0(2), b = 1452.5(2) and c = 639.03(9) pm. The structural results for Sr2H3I are corroborated by EUTAX calculations. For the disordered compound Ba5H2I3.9(2)O2, EUTAX calculations on an approximated, ordered structural model were used to find possible insights into the disorder


2005 ◽  
Vol 60 (9) ◽  
pp. 929-932 ◽  
Author(s):  
Roman V. Gumeniuk ◽  
Lev G. Akselrud ◽  
Yurij B. Kuz’ma

New compounds Ln5(Ag, Ga)19−x (Ln = Gd, Tb) have been found to crystallise with the Rb5Hg19 structure type (space group I4/m). The crystal structures were refined for Gd5Ag1.8Ga15 and Tb5Ag2Ga15.6 from X-ray powder data: a = 9.4635(1), c = 9.8638(2) Å , RI = 0.093 and a = 9.4313(1), c = 9.8491(2) Å , RI = 0.085, respectively. Some positions in the crystal structures of new the compounds are occupied partially.


1995 ◽  
Vol 50 (9) ◽  
pp. 1281-1286 ◽  
Author(s):  
Klaus Kopka ◽  
Rainer Mattes

AbstractThe complexes [(μ-PhCONNCOPh){VOCl(NHNHCOPh)}2 ·5CH3CN, (1), [(μ-PhCONNCOPh){V(dbh)}2]-2CH3CN, (2) and [{VO}2(tbh)], (3) have been prepared by reaction of VCl2(acac)2, acac = acetylaceto n a to (l-), and VCl2(acpn), acpn = propylendiim ino-bis(acetylacetonato(2-)), with benzoylhydrazine. The structures of the centrosymmetric dimeric molecules 1 -3 have been determined by single crystal X-ray diffraction. 1 and 2 contain both doubly deprotonated N,N′-dibenzoylhydrazine as bridging, doubly N,O chelating ligand. In 1 the two remaining coordination sites at the VOCl group are occupied by the hydrazid o(1-) ligand [NHNHCOPh]- . 2 is a non-oxo vanadium(IV) complex. The coordination geometry is approximately trigonal prismatic. The π-back donating effect of the oxo function is substituted by back donation from three negatively charged enolic oxygen atoms. The V - O bond lengths range from 192.0(2) to 193.7(2) pm. 3 contains a unique highly symmetrical octadentate ligand, formed during the synthesis. It is coordinated to two oxovanadin(IV) centers by N,O chelation. The coordination geometry is square pyramidal.


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